[vsnet-grb-info 18948] GRB 170112A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20451
SUBJECT: GRB 170112A: Swift/UVOT Upper Limits
DATE:    17/01/13 16:17:42 GMT
FROM:    Mike Siegel at PSU/Swift MOC  <siegel at swift.psu.edu>

M. H. Siegel (PSU) and B. Mingo (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 170112A
279 s after the BAT trigger (Mingo et al., GCN Circ. 20436).
No optical afterglow consistent with the BAT position
(Lien et al., GCN Circ. 20443) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC           856         1006          147         >20.5
u_FC               279          529          246         >19.9
white              856         6361          344         >21.0
v                 5136         6771          393         >19.2
b                 5956         6156          197         >20.0
u                  279         7338          593         >20.4
w1                5546         7180          393         >19.9
m2                5341         6975          393         >20.2
w2                6366         6566          197         >20.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).